Answer
The pulmonary circuit carries blood to the lungs for gas exchange and returns the blood to the heart while the systemic circuit supplies blood to every organ in the body and then delivers it back to the heart.
The right side of the heart supplies the pulmonary circuit while the left side of the heart supplies the systemic circuit.
Work Step by Step
Blood flows in a figure eight pattern in the body. When blood arrives to the heart in the right atrium, it is deoxygenated. The right atrium dumps the deoxygenated blood into the right ventricle which pumps the blood into the pulmonary arteries. From the pulmonary arteries, the blood is transported to the lungs where gas exchange occurs and the blood is oxygenated. The oxygenated blood is carried back to the heart by the pulmonary veins and dumped into the left atrium. From the left atrium, the oxygenated blood is dumped into the left ventricle and then pumped into the aorta to be sent to the rest of the body.
From this figure eight pattern, we can break up blood flow into two circuits-the pulmonary and systemic circuit. The pulmonary circuit is where the deoxygenated blood goes from the heart to the lungs and then is returned back to the heart. The systemic circuit is where the oxygenated blood is carried from the heart to the tissues and organs,which need the oxygen, and then back to the heart to be reoxygenated.
When we break up the circulatory system into the two circuits, the right side of the heart supplies the pulmonary circuit while the left side of the heart supplies the systemic circuit.
(pg 709)
